Just because we refer to it as the Ice Wall, doesn't mean it looks like a wall in your house. The mountain range is just under 9,000 feet high and that is before you take into consideration that it is buried beneath about 2,000 feet of ice. The barrier for the earth can be beneath miles of flat walkable ice, you can walk across the top of a dam, it's not such a stretch that you'd be able walk across the top of the Ice Wall. Also, this mountain range might not be the entire wall, but part of the wall. If you take into consideration that the earth might be bigger than we actually know, perhaps this mountain range is only the inside edge of the wall.
You still don't get my point.
I don't mean walk across the top as in along it's length, I mean that people have gone from one side of this so called wall to the other by walking on the ice that is covering it.
The range is so much a wall as an underwater trench is a wall.
It doesn't stop anything.
The entire theory of the ice wall requires that there is a actual wall of ice/mountains keeping the atmosphere in place and not leaking off into space.
You range currently looks like this:
_________________ <- land we walk on, the known surface of Antarctica at that point.
few
thousand
feet
_____/\/\/\/\______ <- Your "ground level" where your mountains are, you'll probably only be able to see the peaks above the surface.
If we can cross this wall so easily and record exactly how big Antarctica is via navigation and walking from one side to the other, how can there be a mass amount of land hiding somewhere behind a wall that only exists beneath the surface.
ED: Here you go, hopefully you understand now.

Oh look, no hidden Garden of Eden or anything.
